Vespa tropica is a tropical species of Vespa found in Southeast Asia. V. tropica wasps were collected from rural provinces of Cambodia, and their total RNA and venom were extracted on site. To search for novel substances in venom, a subtracted cDNA library specific to the venom gland and sac was constructed and venom protein was analyzed by nano-LC-MS/MS. A total of 1127 expressed sequenced sequence tags (ESTs) were sequenced and assembled into 572 contigs (152 multiple sequences and 420 singletons). The short venom peptides were identified to be encoded from 5 contigs (43 ESTs) by proteomic analysis. In addition, putative antimicrobial peptides together with typical major components of wasp venom (venom allergen 5, mastoparan-like peptide, serine protease, and hyaluronidase) were identified in the EST Library. Additional in-depth annotation would be required for further characterization of many unidentified genes found in the EST library.

The silkworm-baculovirus expression system has distinct advantages, such as a high yield and safe usage in vertebrates. Here, we report a novel strategy for the large-scale production of a classical swine fever virus (CSFV) envelope glycoprotein E2 in the larvae of a baculovirus-infected silkworm, Bombyx mori. We constructed a recombinant B. mori nucleopolyhedrovirus (BmNPV) that expressed recombinant polyhedra together with the N-terminal 179 amino acids of CSFV E2 (E2ΔC). BmNPV-E2ΔC-infected silkworm larvae expressed native polyhedrin and approximately 44-kDa fusion protein that was detected using both anti-polyhedrin and anti-CSFV E2 antibodies. Electron and confocal microscopy both demonstrated that the recombinant polyhedra contained both the fusion protein and native polyhedrin were morphologically normal and contained CSFV E2ΔC. The CSFV E2ΔC antigen produced in BmNPV-E2ΔC-infected silkworm larvae reached 0.68 mg per ml of hemolymph and 0.53 mg per larva at 6 days post-infection. Six-week-old female BALB/c mice that were immunized with the E2ΔC protein purified from solubilized recombinant polyhedraelicited CSFV E2 antibodies, which indicated that the CSFV E2ΔC protein from recombinant polyhedra was immunogenic. The virus neutralization test showed that the serum from mice that were treated with E2ΔC protein from recombinant polyhedra contained significant levels of virus neutralization activity. These results demonstrate that the present strategy can be used for the large-scale production of CSFV E2 antigen.

Body and head lice (Pediculus humanus humanus and Pediculus humanus capitis, respectively) are typical ectoparasites of humans. They differ not only in the ecological habitat but also in the vector competence in spite of their conspecific nature. Only body lice transmit several bacterial pathogens to humans, including Bartonella quintana, Rickettsia prowazekii and Borrelia recurrentis. In this study, the proliferation rates of two model bacteria, a gram positive Staphylococcus aureus and a gram negative Escherichia coli, were determined following bacterial challenge by cuticular injection. Both bacteria proliferated rapidly in body lice at the early stage of bacterial challenge but not in head lice, suggesting that head lice have more sensitive immune responses to these bacteria. In vivo phagocytosis assay revealed that head lice have much higher phagocytic activity against E. coli than body lice whereas only slight differences in phagocytic activity against S. aureus were observed between the two lice species. Taken together, these findings suggest that the reduced phagocytosis activity of body lice contributes, at least in part, to their higher vector competence.

The Samia cynthia ricini (Lepidoptera: Saturniidae) is a commercial silk-producing insect belonging to an insect family Saturniidae in Bombycoidea. The species that has presumably been originated in India, is distributed in India, China, and Japan. Unlikely domestic silkworm the prime host plant for the species is a castor-oil plant (Ricinus communis in Euphorbiaceae). Recently, the eri-silkworm also is reared in Korea and is expected to be utilized for a diverse purpose. In this report, we present the complete mitochondrial genome of the species with the emphasis of a few major characteristics. The 15,384-bp long S. cynthia ricini (Lepidoptera: Saturniidae) mitochondrial genome was amplified into three long overlapping fragments (from COI ~ ND4, ND5 ~ lrRNA, and lrRNA ~ COI) and subsequent several short fragments using the long fragments as temperate. The primers for both long and short fragments were designed solely for lepidopteran genomes, without any species-specific primers. As a usual the genome is composed of 37 genes: 13 protein-coding genes (PCGs), two rRNA genes, and 22 tRNA genes, and one large non-coding region termed the A+T-rich region. Arrangement of the genome is identical to those of other lepidopteran mitochondrial genome, but this differs from the common arrangement found in a diverse insect order, by the movement of tRNAMet to a position 5’- up stream of tRNAIle. Unlikely previous report on the start codon for COI gene in Lepidoptera S. cynthia ricini COI gene starts with typical ATT codon located between tRNATyr and the beginning region of COI gene. The 22 tRNAs that are interspersed throughout the mitogenome ranged in length from 62 to 71 bp. All tRNAs but tRNASer(AGN) were shown to be folded into the expected cloverleaf secondary structures. More detailed structural and phylogenetic analyses among Bombycidae and Saturniidae in connection with other families in the Bombycoidea will be performed soon

From the methanol crude extracts of the tree of heaven (Ailanthus altissima) leaves, the antifeedant substance was isolated and bioassayed with different concentrations against diamondback moth (Plutella xylostella) larvae. The antifeeding activity was evaluated by measuring the feeding area during 24 hr after inoculation. Methanol extracts showing antifeeding activity at 5000 ppm was subsequently fractionated into hexane, chloroform, ethyl acetate and water layer. Third larvae of diamondback moth was tested to each fraction layer. Chloroform layer shows the highest antifeeding activity and the layer was purified by silica gel open column chromatography. The C22 and C23 fractions showed higher antifeeding ratio with 96 and 86%, respectively, and then these two fractions were re-isolated by ODS open column chromatography. As a result, both fractions in methanol 40% (v/v) showed antifeeding ratio over 90%. The C221 fraction showed insecticidal activity in all fraction, however, C231 fraction was showed the antifeeding activity only in C2311 fraction. The C2311 fraction judging to have antifeeding activity was re-isolated and purified by HPLC and recycling, and finally obtained the bioactive substances (C23111) with antifeeding ratio with 88%. The structure of bioactive materials isolated was confirmed by LC-mass and 1H-NMR(500 MHz), 13C-NMR(100 MHz).

To find an alternative for synthetic pesticides, methanol extract from plant samples were tested for their insecticidal activity against insect. The extract of Asiasarum sieboldii had strongly insecticidal activity against Plutella xylostella. Roots of A. sieboldii were extracted with methanol, and the concentrated extract was partitioned with n-hexane, ethylacetate, n-buthanol and H2O. The highest activity was shown in the hexane fraction. Activity-guided fractionation led to the isolation of two amides from hexane fration through the repeated silica gel column chromatographic separations. From the interpretation of spectropic data including NMR, MS, IR, the chemical structures of compounds were determined as dodeca-2E,4E,8Z,10Z-tetraenoic acid isobutylamide and dodeca-2E,4E,8Z, 10E-tetraenoic acid isobutylamide. These compounds showed insecticidal activity on P. xylostella by 96.7% at 100ppm. The liquid formulation controlled on cabbage effectively. The extract and compounds from A. sieboldii showed insecticidal activity against Nilaparvata lugens. As a naturally occurring pesticide, A. sieboldii could be useful as a new botanic insecticide.

The aim of this study was to evaluate light emitting diodes (LEDs) as the potential attractants against Spodoptera exigua on various wavelengths, light intensity and light duration, and compared to that of commercial control, flourescent lamp. The phototactic response to S. exigua was tested by single and complex wavelengths. The single wavelengths were composed as follows: blue (470 nm), green (520 nm), yellow (590 nm) and red (625 nm). The complex wavelengths was combined with two single wavelengths, such as blue-green, blue-yellow, blue-red, green-yellow, green-red and yellow-red. When the optimal light condition was investigated, the all light treatments attracted the highest number of S. exigua at 40 lux intensity and 60 min duration. Based on the single wavelengths under optimal light condition, the green LED exhibited the highest attraction rate (88.9%), followed by blue (81.1%), yellow (63.3%) and red (56.7%), respectively. In case of complex wavelengths under same conditions, the bluegreen complex (93.3%) had the significantly highest attractive activity, whereas blue-yellow, blue-red, green-yellow, green-red and yellow-red wavelengths were slightly decreased in comparison with single wavelengths. These data clearly show that blue-green complex had the greatest attraction against S. exigua.

Sweet potato whitefly, Bemisia tabaci, is one of the most common and critical green house pests in the world. The object of this study was to evaluate the attraction effect of various colored high power light emitting diodes (HPLEDs) against B. tabaci. These insects with diverse HPLEDs were examined by LED equipped chamber in the dark room at 27±0.5℃ and 60±5% relative humidity. Evaluated light-sources were blue (470±10 nm), green (520±5 nm), yellow (590±5 nm) and red (625±10 nm) HPLEDs, and tested with various illuminance intensity at 20, 40, 60, 80 and 100 lux. Base on the attraction rates, the green (94.4%) HPLED was the most effective against B. tabaci, followed by yellow (78.9%), blue (71.1%) and red (60%) HPLEDs. Furthermore, these data show that both the 80 lux intensity and 40 min light-exposure time using the green HPLED was the most suitable for attraction of B. tabaci. Putting all results, our data will provide the useful information for eco-friendly pest control against B. tabaci.

The emulsion and micro-encapsuled formulation from three essential oils, cassia, thyme white and lemon grass were tested for their insecticidal activities against Lycoriella ingenua (Dufour) adults at 0.3% concentration. As a result, the micro-encapsules than emulsion formulation was confirmed to show greater activity. Based on this result, insecticidal activities at several levels of concentration were examined, resulting in more than 80% insecticidal activity after 30 minutes at 0.6% level of cassia formulation. And also, insecticidal activity of three oil-based micro-encapsuled formulations lasted for up to 12 hours at 0.9% concentration. The main ingredients derived from three essential oils were evaluated on the insecticidal activity against Lycoriella ingenua. As a result, in case of thymol from thyme white, it showed more than 80% mortality after over 30 minutes at 0.25%, and in cinnamic aldehyde and citral, exhibited 88% and 82% mortality after 30 minutes at the 0.5% level, respectively. These three compounds were examined for whether the insecticidal activity was maintained depending on being over time. In case of thymol, it maintained good insecticidal activity against Lycoriella ingenua at 0.5% level until 120 hours, while cinnamic aldehyde and citral showed lower activity after 12 hours.

The insecticidal effect for several commercially available environment friendly agricultural materials (EFAMs) is investigated to Cnaphalocrocis medinalis, Narana aenescens, Pseudaletia unipuncta and Parnara guttata on rice. In the insecticidal effects for 2-3rd instar larvae of lepidopteran after treatment with 19 EFAMs, more than 95% of mortality rate showed 5 EFAMs in C. medinalis, 12 EFAMs in N. aenescens, 9 EFAMs in P. unipuncta, and 14 EFAMs in P. guttata, respectively. Among 4 EFAMs selected for C. medinalis in indoor, more than 70% in control effect is seen EFAM-B(85.2%), EFAM-I(79.1%) and EFAM-M (78.3%), respectively, in rice field. The insecticidal effect for EFAMs is investigated to Nilaparvata lugens, Laodelphax striatellus and Nephotettix cincticeps on rice. In the insecticidal effects for 2-3rd nymph and adult after treatment with 19 EFAMs, more than 95% of mortality rate showed 5 EFAMs in N. lugens adult, 7 EFAMs in N. lugens nymph, 6 EFAMs in L. striatellus, and 5 EFAMs in N. cincticeps, respectively. Insecticidal effect for N. lugens was sustained until 10 day in rice treated with 7 EFAMs selected in indoor. Among them, EFAM-L, EFAM-P and EFAM-R was sustained in low density until 27 day. But EFAM-D, EFAM-L, EFAM-N and EFAM-S showed high density until 27 day and additional control was needed.

Biological control of rice insect pest is an important component of an IPM program. There are many species of natural enemies which contribute to the suppression of rice pest populations below economic injury levels. In order to use biological control more efficiently, it is a need to identify beneficial species and determine their roles in possible regulation of insect pests. There is a rich complex of biological control agents in rice and bund. This research was carried out to investigate the population density of insect pests and natural enemies in the rice field and bund. A total of 7 pest species and 15 natural enemy species were collected in the rice field. 10 pest species and 20 natural enemy species were collected in the bund, also. Changes in population density of insect pests and its prey were investigated in the rice field and bund. Population densities of insect pests were low at any time during the rice growth period in the field. This could be the high density of natural enemies. Bunds served as refuge for natural enemies when rice maturity. There are rich complex of biological control agents in rice field and bund. So, when we practice integrated pest management(IPM) of rice insect pests, we should use various natural enemies.

We have gathered rice grain and bran from conventional mills and RPC(Rice Processing Complex) for the survey of stored grain insect pests. Maize weevil(Sittophilus zeamais) is the dominant species among the stored grain insect pests of the rice grain and bran. Under three constant temperatures, 15, 20 and 25℃, developmental periods from egg to adult were 43.0, 37.5 and 29.2 days, respectively. With egg periods being 9.6, 7.3 and 5.2days, and larval periods being 25.2, 21.8 and 19.8days, and adult periods being 126.1, 110.3 and 108.6days, respectively. The adults of Maize weevil feed basically on the same the foods as the larvae but not as restricted in their diets because the larvae need to develop inside whole grains. Feeding of S. zeamais adult usually began 3∼4 days after emergence at 25℃. Then adult feeding ca. one rice a day, reaching a peak of 20∼40days after emergence.

Field research was undertaken for recovering mosquito larval mermithid parasite, Romanomermis species in rice fields in 54 different areas in period of May through October, 2009. Of 54 area rice fields surveyed, Romanomermis sp. recoveries were made from 4 areas. 32 Anopheles mosquito larvae, malaria disease vector were infected and died from samples collected in Pochon area, and a total of 10 Culex mosquito larvae, house frequenting mosquito were infected to death in 3 different areas, Gimpo, Sangju and Gurae, respectively. On the basis of positive natural infection record, an intensive host-parasite occurrences and/or population study was surveyed in foci area of Pochon in small pond (P) and Rice paddies (A and B) during 5 months till end of October. The natural mermithid infection was continuously occurred from June through October in weekly samples, however the rate of infection was appeared higher in June-July, thereafter the rate gradually decreased in progress of the season. The highest natural infection rate was observed from the Pond 9.1% followed by Rice paddy "A" 5.2%, Rice paddy "B" 2.4%, respectively. Including 2 other Rice paddies "C" and "D", a total mosquito larvae collected was 3,270, an overall average natural infection rate was recorded as 3.7% (121 Anopheles mosquito larvae infected).

Spatio-temporal distribution pattern of an ambrosia beetle, Platypus koryoensis (Murayama) which is vector of Raffaeleaquerci-mongolicae K.H. Kim et al, a causative agent for Korean oak wilt (KOW) was examined in the stand level. Spatial distribution of P. koryoensiswas influenced by their density. Relationship between degree of aggregation and density was positively correlated when the density was extremely low or high whereas the relationship was reverse when the density was intermediate. Patch of P. koryoensis formed around or near dead trees or partial dead trees, suggesting these trees indicated epicenter of P. koryoensis. Fraction of trees attacked by less than 100 individual of P. koryoensis in the stand per year increased abruptly whereas fraction of trees attacked over 1,000 individuals of P. koryoensis increased gradually. Our results showed that the dead trees would be an epicenter of P. koryoensis and the number of trees killed by the ambrosia beetle would be reduced by lowering total population of the ambrosia beetle around the epicenter.

The developmental time and survival of overwintering larvae of Monochamus saltuarius were studied at 7 constant temperatures (16, 20, 23, 25, 27, 30, 34℃), and a photoperiod of 16 : 8 (L : D) h. The total mortality of overwintering M. saltuarius was lowest at 27℃ (7%) and highest at 34℃ (93%). The total developmental time decreased with increasing temperature between 16℃ (49.48 days) and 34℃ (13.00 days). The relationship between the developmental rate and temperature was fitted by five nonlinear developmental rate models (Logan 6, Lactin 1, 2 and Briere 1, 2). The nonlinear shape of temperature development was best described by the Briere 1 model (r2=0.99). The developmental variation of overwintering larvae was well described by the three-parameter Weibull distribution model (r2=0.98). The temperature-dependent developmental models of M. saltuarius developed in this study could be used to predict emergence period of the adult, or to develop a population dynamics model of M. saltuarius.

The pear psylla, Cacopsylla pyricola Foerster (Homoptera: Psyllidae), is a serious insect pest of commercial pear crops. The species, which resides on pear trees throughout its life cycle, is rapidly spreading in some regions of the world. Given the life cycle, it is unclear how such a rapid spread has been facilitated. Presently, the population genetic structure of the species including genetic diversity and gene flow was studied to understand the nature of dispersal and field ecology of the species. Pear psylla was collected from several pear orchards in Korea. The 658-bp region of mitochondrial COI gene and the 716-bp long complete internal transcribed spacer 2 (ITS2) of the nuclear ribosomal DNA were sequenced. Unlikely other previously studied insect pests, the COI-based genetic diversity of the pear psylla was extremely low (maximum sequence divergence of 0.15%). This finding allowed us to conclude that the species may have been introduced in Korea relatively recently, possibly with the phenomenon of genetic bottlenecks. ITS2 sequence-based analyses of phylogeny, population differentiation, gene flow, and hierarchical population structure all concordantly suggested that the pear psylla populations in Korea are neither genetically isolated nor hampered for gene flow. These genetic data are concordant with the dispersal of an overwintering winterform morph outside the non-pear habitat in the fall and the possibility of subsequently longer distant dispersal.